Originally Posted by
2wdBlazer
The 17's have a little notch in the side of the center cap so it pops off easy. The 18's which I have are notch-less.
If you look in thread you posted, both 17 and 18 inch come with a notch on the center cap. The widespoke avus has the notch in both 17 and 18 inch. The thin spoke avus does not have it on either diameter, so who knows what they are.